At least 31 people have been killed and dozens more injured in two explosions in Iraq, including one targeting security officials just south of the capital Baghdad.

In the first explosion on Monday, a suicide car bomber killed at least 21 Shia militia members and injured 37 others in a town 50km from Baghdad, a day fighters from the Islamic State of Iraq and the Levant (ISIL) were pushed out of the strategic area.

Sources told Al Jazeera a suicide bomber detonated an explosives-rigged Humvee near a checkpoint manned by security forces and allied militia members in Jurf al-Sakhr.

ISIL seized the strategic Sunni town in July, that lies on a road usually taken by Shia pilgrims when they head to the holy city of Karbala.

Pilgrims will be taking the route in the coming weeks to commemorate the death of the Prophet Muhammad's grandson, Imam Hussein, who's shrine is in Karbala.

In Monday's second incident, a bomb-laden car exploded in Baghdad's Karrada district, killing at least 15 people and injuring dozens more, police and medical sources said.

Al Jazeera's Imran Khan, reporting from Baghdad, said a loud explosion echoed across the capital as the blast hit a residential area that has frequently been targeted in recent months.

The attack took place on a street with shops and restaurants, home to both Shia and Sunni Muslims as well as other sects and ethnic groups.

Since early this year, Iraq has been facing increasing levels of violence targeting Shia neighbourhoods as ISIL seeks to consolidate its control over areas in the country's west and north.